B, N dual-doped porous carbon nanoframeworks as bifunctional peroxymonosulfate activators for ultrafast adsorption and decomposition of microcontaminants in water

The limited mass transfer kinetics and low inherent catalytic activity of catalyst are the main bottlenecks to boost the heterogeneous activation efficiency of peroxymonosulfate (PMS). Herein, B, N dual-doped porous carbon (BNC-X) nanoframeworks with large specific surface area (1085.3–1127.6 m² g⁻¹) and dual-functional N-B sites are constructed as PMS activators to achieve ultrafast adsorption and oxidation of microcontaminants. The optimized BNC-8 displays greatly improved adsorption and catalytic activity, affords an ultrahigh tetracycline (TC) adsorption capacity of 1413 mg g⁻¹, and can remove 83.7 % of concentrated TC (100 mg/L) just within 10 min, outperforming most state-of-the-art carbon materials. The preconcentration of reactants on the surface of catalyst develops a confined reaction space for PMS and target contaminant to promote the in-situ activation of PMS to selectively produce surface-bound radicals, and accelerate the decomposition of organic pollutant with an elevated mass transfer rate. The adsorption kinetics and theoretical calculations reveal that the incorporation of B into N-doped carbon network develops nanoscale adsorption-oxidation dual centers (N-B sites), tunes the chemical and electronic properties of carbon matrix, as well as maximizes the utilization efficiency of PMS, thereby facilitating the generation of surface-bound SO₄•⁻ through lowering the energy barrier thermodynamically for PMS activation. Additionally, the cooperation of catalytic oxidation of BNC-8 and membrane separation enables rapid removal of flowing contaminant. This work integrates the advantages of adsorption and catalytic oxidation in PMS activation and develops a valuable candidate for water treatment.